Let r1 and r2 be the radii of the largest and smallest circles, respectively, which pass through the point (–4,1) and having their centres on the circumference of the circle x2+y2+2x+4y−4=0. Ifr1r2=a+b√2, then a+b is equal to:

Let r1 and r2 be the radii of the largest and smallest circles, respec

1.	Let r1 and r2 be the radii of the largest and smallest circles, respectively, which pass through the point (–4,1) and having their centres on the circumference of the circle x2+y2+2x+4y−4=0. Ifr1r2=a+b√2, then a+b is equal to:
Answer» Let $r_{1}$ and $r_{2}$ be the radii of the largest and smallest circles, respectively, which pass through the point $(- 4, 1)$ and having their centres on the circumference of the circle $x^{2} + y^{2} + 2 x + 4 y - 4 = 0.$ If $\frac{r_{1}}{r_{2}} = a + b \sqrt{2,}$ then $a + b$ is equal to: